Izvorni znanstveni članak
Preparation of Silica Nanoparticles and Its Beneficial Role in Cementitious Materials
L. P. Singh
; CSIR-Central Building Research Institute (CBRI), India
S. K. Agarwal
; CSIR-Central Building Research Institute (CBRI), India
S. K. Bhattacharyya
; CSIR-Central Building Research Institute (CBRI), India
U. Sharma
; CSIR-Central Building Research Institute (CBRI), India
S. Ahalawat
; CSIR-Central Building Research Institute (CBRI), India
Sažetak
Spherical silica nanoparticles (n‐SiO2) with
controllable size have been synthesized using
tetraethoxysilane as starting material and ethanol as
solvent by sol‐gel method. Morphology and size of the
particles was controlled through surfactants. Sorbitan
monolaurate, sorbitain monopalmitate and sorbitain
monostearate produced silica nanoparticles of varying
sizes (80‐150 nm), indicating the effect of chain length of
the surfactant. Increase in chain length of non‐ionic
surfactant resulted in decreasing particle size of silica
nanoparticles. Further, the size of silica particles was also
controlled using NH3 as base catalyst. These silica
nanoparticles were incorporated into cement paste and
their role in accelerating the cementitious reactions was
investigated. Addition of silica nanoparticles into cement
paste improved the microstructure of the paste and
calcium leaching is significantly reduced as n‐SiO2 reacts
with calcium hydroxide and form additional calcium‐
silicate‐hydrate (C‐S‐H) gel. It was found that calcium
hydroxide content in silica nanoparticles incorporated
cement paste reduced ~89% at 1 day and up to ~60% at 28
days of hydration process. Synthesized silica particles
and cement paste samples were characterized using
scanning electron microscopy (SEM), powder X‐ray
diffraction (XRD), infrared spectroscopy (IR) and
thermogravimetric analysis (TGA).
Ključne riječi
Amorphous materials; Nano‐silica; Nanostructures; Sol‐gel chemistry
Hrčak ID:
71558
URI
Datum izdavanja:
15.6.2011.
Posjeta: 10.679 *